Study On The Effect Of Watermelon With Coupling Of Water And Fertilizer Under Mulch Drip Irrigation In Ninngxia Tongxin Drought Region

In view of the problem of low water and fertilizer use efficiency of watermelon in dry land in Tongxin,Ningxia,choosing the irrigation of under mulched drip irrigation,setting three irrigation quotas of 450 m3/hm2(A1),900 m3/hm2(A2),and 1350 m3/hm2(A3),three fertilizer amounts of 225 kg/hm2(B1),450 kg/hm2(B2),and 675 kg/hm2(B3),for a total of 9 treatments.Researching on the efficiency on different combinations of water and fertilizers on the growth,yield,water use efficiency,quality,soil moisture dynamics and water consumption of watermelon,and the water and fertilizer programs suitable for watermelon cultivation in the area were selected.The main results are as follows:(1)In the whole growth period of watermelon,the soil moisture content in 0-30 cm soil layer has the largest change,and in 30-40 cm soil layer changes slowly.After the swelling period,the water content of soil treated with A1 was the smallest,and A3 treatment was the highest.(2)Through the regression analysis,irrigation quota and fertilization amount had a significant effect on the stem diameter,main vine length,dry matter accumulation and yield of watermelon.And the order of influence was:irrigation quota>fertilization amount>irrigation quota with fertilization amount.A2B2 treatment had the largest stem diameter(11.89±0.17 mm),A2B3 had the largest main vine length(244.83±6.35 cm),A3B2 had the largest dry matter accumulation(113.90±2.17 g),A2B2 had the highest yield(88.23±4.41 t/hm2),A1B2 had the highest water use efficiency(4.79 kg/m3).A2,A3 and B2,B3 treatments help to promote watermelon growth,increase yield and water use efficiency of watermelon.(3)Under A1,A2 and B1,B2 treatments conditions,the soluble solid content of watermelon is higher.The soluble sugar content of watermelon of A2B2 was the highest(9.64%),and Vitamin C of watermelon was the highest(7.79 mg/100g).Different water with fertilizer treatments had no significant effect on total acid content in watermelon fruits(P>0.05).Therefore,under the irrigation quota 900m3/hm2 and fertilizer amount 450 kg/hm2 can improve the quality of watermelon.(4)The main ingredient analysis method was used to comprehensively evaluate the water with fertilizer coupling effect of drip irrigation under film.The results showed that the irrigation quota was 900 m3/hm2 and the fertilizer amount was 450 kg/hm2.And under this treatment had the highest comprehensive score and could be used as the optimal water and fertilizer combination.In this paper,through the field positioning experiment,the choose of suitable water and fertilizer program for the cultivation of watermelon in this area was provided a scientific basis for the promotion of "Saving water and fertilizers,increasing the yeild" in the Yellow River Pumping irrigation area in Ningxia.